Main cap Bolts for GM LS1 LS2 LS3 LS6 LS99 Engines. Includes 10 inner main bolts and 10 outer main bolts for Windage tray, 10 Main Cap side bolts and (16) connecting rod bolts with Cap Retention Style: Cap screw 6 point. New style, Contains Retaining ring. These bolts are from the same supplier to GM. These replace OEM 12560272,12560273, 12556127, 11570662 bolts.